Renewable Energy Options for householders. Andrew Cooper

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1 Renewable Energy Options for householders Andrew Cooper

2 Overview Why Microgeneration? Overview of Microgeneration Technologies with case studies Funding

3 Why Microgeneration? National strategic context Energy White Paper/Energy Review Microgeneration Strategy Climate Change and Sustainable Energy Act

4 What is Microgeneration? Small-scale renewable energy technologies, distributed generation, embedded generation, microgeneration, microrenewables Defined by Energy Act 2004 Electricity/Power under 50kW Heat/Thermal under 45kW Established and proven technologies

5 Overview of Technologies Power Technologies Solar PV Wind Hydro Thermal Technologies Biomass Solar Thermal Heat Pumps

6 Technology - Solar PV Solar photovoltaic (PV) uses energy from the sun to create electricity to run appliances and lighting. PV requires only daylight to generate electricity. PV systems use cells to convert solar radiation into electricity. The PV cell consists of one or two layers of a semi conducting material, usually silicon. When light shines on the cell it creates an electric field across the layers, causing electricity to flow.

7 Solar Energy in the UK total average solar radiation falling on one square metre surface inclined at 30 degrees to the horizontal, measured in kilowatt hours Solar Heating systems will typically convert 40 to 50% of the solar energy falling on the solar collectors into useful heated water

8 Seasonal Solar Variation

9 Technology - Solar PV PV arrays now come in a variety of shapes and colours, ranging from grey 'solar tiles' that look like roof tiles, to panels and transparent cells that you can use on conservatories and glass to provide shading as well as generating electricity.

10 Case study University of Leeds

11 Technology - Wind Modern wind turbines use the wind's lift forces to turn aerodynamic blades that turn a rotor which creates electricity. Wind power is proportional to the cube of the wind's speed, so relatively minor increases in speed result in large changes in potential output. Individual turbines vary in size and power output from a few hundred watts to two or three megawatts

12 Technology - Wind For some newer wind turbines, particularly those designed for mounting on buildings, there may not be (or only limited) independent long-term performance data verifying performance claims. Planning issues such as visual impact, noise and conservation issues also have to be considered. System installation normally requires permission from the local authority.

13 Case study Bronte School Wind Cluster, Bradford Spen Valley Sports College, Huddersfield

14 Technology - Hydro Hydro-power systems convert potential energy stored in water held at height to kinetic energy (or the energy used in movement) to turn a turbine to produce electricity. A micro hydro plant is below 100kW. Improvements in small turbine and generator technology mean that micro hydro schemes are an attractive means of producing electricity. Useful power may be produced from even a small stream.

15 Technology - Hydro Energy available in a body of water depends on the water's flow rate (per second) and the height (or head) that the water falls. Output will depend on how efficiently the turbine converts the power of the water into electrical power (maximum efficiencies of over 90% are possible but for small systems 50% is more realistic).

16 Case study Gibson Mill, Calderdale

17 Technology - Biomass Biomass is often called 'bioenergy' or 'biofuels and produced from organic materials, either directly from plants or indirectly from industrial, commercial, domestic or agricultural products. Biofuels fall into two main categories: Woody biomass includes forest products, untreated wood products, energy crops, short rotation coppice (SRC), e.g. willow. Non-woody biomass includes animal waste, industrial and biodegradable municipal products from food processing and high energy crops, e.g. rape, sugar cane, maize

18 Technology - Biomass Stand-alone stoves providing space heating for a room. These can be fuelled by logs or pellets but only pellets are suitable for automatic feed. Generally they are 6-12 kw in output, and some models can be fitted with a back boiler to provide water heating. Boilers connected to central heating and hot water systems. These are suitable for pellets, logs or chips, and are generally larger than 15 kw.

19 Technology - Biomass Fuel: It's important to have storage space for the fuel, appropriate access to the boiler for loading and a local fuel supplier. Flue: The vent material must be specifically designed for wood fuel appliances, chimneys can be fitted with a lined flue. Smokeless zone: Wood can only be burnt on exempted appliances, under the Clean Air Act.

20 Case study Biomass fuel conversion trial: coal to pellets Ilkley Grammar & Outwood Grange

21 Technology Solar Thermal Solar water heating systems use heat from the sun to work alongside your conventional water heater. The technology is well developed with a large choice of equipment to suit many applications

22 Technology Solar Thermal For domestic hot water there are three main components: solar panels, a heat transfer system, and a hot water cylinder. Solar panels - or collectors - are fitted to your roof. They collect heat from the sun's radiation. The heat transfer system uses the collected heat to heat water. A hot water cylinder stores the hot water that is heated during the day and supplies it for use later.

23 Case study Calder High School

24 Technology Heat Pumps Heat pumps are familiar to us - fridges and air conditioners are two examples. Ground source heat pumps (GSHP) transfer heat from the ground into a building to provide space heating and, in some cases, to pre-heat hot water. For every unit of electricity used to pump the heat, 3-4 units of heat are produced. As well as ground source heat pumps, air source and water source heat pumps are also available.

25 Technology Heat Pumps There are three important elements to a GSHP: 1) The ground loop. This is comprised of lengths of pipe buried in the ground, either in a borehole or a horizontal trench. 2) A heat pump 3) Heat distribution system. Consisting of under floor heating or radiators for space heating and in some cases water storage for hot water supply.

26 Case study Copt. Hewick in Harrogate

27 Factors to consider when calculating payback Capital cost Any grant contributions Assumed hot water produced by solar Cost of fuel displaced Lifetime of the product Maintenance Cost of fuel displaced over the lifetime of the product Impact on house value

28 Standards REAL Code Microgeneration Certification Scheme